53 research outputs found
Factors affecting the production of a single-chain antibody fragment (SCFV) by Aspergillus awamori in stirred tank reactors
Recombinant antibodies have in recent years proved their potential to be an important class of therapeutics. Potential applications demand large doses for administration and therefore production of antibody fragments in microbial or fungal systems has become important. In this study, a recombinant strain of Aspergillus awamori, producing anti- lysozyme scFv under the control of the xylanase promoter, was used. A fermentation strategy was created for the production of the antibody fragments by a fed-batch process, based on the investigation of parameters which affected production, namely growth medium composition, induction regime and protease production. Experiments with the time of induction showed that the optimum results are achieved when induction is started in the late exponential phase (21 hours after inoculation) improving the titre of the product from 14.5 mg L-1, obtained in the early exponential phase (7 hours after inoculation) to 16.2 mg L-1. A 100% increase of the carbon (fructose) and nitrogen (ammonium sulphate) sources in the growth medium resulted in an increase in product concentration from 16.2 mg L-1 to 108.9 mg L-1 and an increase in maximum dry cell weight from 7.5 g L-1 to 11.5 g L-1. A 50% reduction in the concentration of the inducer resulted in an increase in the specific product yield from 10 mg g-1 dry cell weight to 12 mg g-1 Proteolytic enzymes were produced during the fermentation up to concentrations equivalent to 1.4 g L-1 trypsin but storage experiments showed that they had no detrimental effect on the concentration of the antibody fragment. The process was scaled-up to 75 L where maximum scFv concentration reached 160 mg L-1 after 42 hours of fermentation. Specific yield and specific productivity were increased by 100% and 50% respectively, while volumetric productivity decreased by 500%. Pellet dimensions were the same. A comparison between production of the same scFv antibody fragment in A. awamori and E. coli was carried out
Molecular, biochemical and genetic investigation of recurrent miscarriage
Recurrent miscarriage (RM), defined as three or more (or two or more) consecutive miscarriages before 20 weeks, affects (depending on the definition) 1-5% of couples. In the present studywe analysed a sample of 120 patients with >2 miscarriages before 20 gestational weeks for proven and likely causes of recurrent miscarriage and, when indicated, we compared the prevalence ofthe factors under study with that of a control group including women with >2 successful pregnancies without a history of pregnancy loss. The research arm included investigation for thrombophilic mutations (factor II G20210A mutation, Factor V Leiden, Factor V A1299H(A4070G) mutation of HR2 haplotype, MTHFR C677T polymorphism and MTHFR A1298C polymorphism) and for abnormalities of the mechanism of clotting - fibrinolysis (PAI activityand PAI-1 4G/5G polymorphism). One or more accepted causes for recurrent miscarriage were found in 25.8% of the cases. None of the five common thrombophilic mutations under study (factor II G20210A mutation, Factor V Leiden, Factor V A1299H (A4070G) mutation of HR2 haplotype, MTHFR C677T polymorphism and MTHFR A1298C polymorphism) was associated with statisticallyincreased risk for recurrent miscarriage. Factor V Leiden (OR 1.75, 95% CI 0.41 - 7.55) and factor II G20210A mutation (OR 2.63, 95% CI 0.49 - 13.90) are two possible exceptions to this; however, the small size of our sample prevented them from reaching statistical significance. The activity of PAI was not significantly different between the groups (p=0.61). However, the distribution of PAI-1 4G/5G polymorphism was significantly different (p=0.01) and homozygosity 4G/4G was more common among controls (p=0.014). Linear regression analysis showed that protein C level, homozygosity 4G/4G and age are the only significant predictors for PAI activity. Protein C level accounts for 22% of the variability in PAI activity and 4G/4G haplotype for only 6%. No responsible causative factor was found in 74.2% (95% CI 66.3 - 82.0) of our patients. Forty-one patients from this subgroup achieved pregnancy, for which the outcome is known, within the first year after investigation. Excluding two cases of ectopic pregnancy, the overall successful pregnancy rate was 79.5% (95% CI 66.8- 92.1). Although the small size of this sample prevents formal statistical analysis, a simple descriptive analysis indicates that the prognosis in a subsequent pregnancy is mainly associated with the age of the patient and the number of previous miscarriages.Οι καθ' έξιν αποβολές παρατηρούνται στο 1-5% των ζευγών που ειχειρούν να τεκνοποιήσουν. Αναλύσαμε δείγμα 120 ασθενών με >2 αποβολές 2 παιδιά χωρίς ιστορικό αποβολών. Τα υπό διαρεύνηση αίτια περιλάμβαναν τις θρομβοφιλικές μεταλλάξεις FN G20210A, Factor V Leiden, MTHFR C677T, FV A1299H (R2), και MTHFR A1298C, καθώς και ανωμαλίες του μηχανισμού πήξης - ινωδόλυσης (δραστικότητα του PAI και πολυμορφισμός 4G/5G για το γονίδιο του PAM. Ένα ή περισσότερα αποδεδειγμένα αίτια καθ' έξιν αποβολών βρέθηκαν συνολικά στο 25.8% των περιπτώσεων. Καμία από τις πέντε κοινές θρομβοφιλικές μεταλλάξεις που μελετήσαμε, μονή ή σε συνδυασμό, δεν σχετίζεται με στατιστικά σημαντική αύξηση του κινδύνου καθ' έξιν αποβολών. Πιθανώς σε αυτό αποτελούν εξαιρέσεις ο παράγοντας V Leiden (λόγος αναλογιών [OR] 1.59, 95% διάστημα εμπιστοσύνης [CI] 0.37-6.82) και η μετάλλαξη G20210A του γονιδίου της προθρομβίνης (OR 2.38, 95% CI 0.45-13.90), αν και το μέγεθος του δείγματος δεν επέτρεψε σε αυτές την επίτευξη σημαντικότητας, Η δραστηριότητα του αναστολέα του ενεργοποιητή του πλασμινογόνου (PAI) δεν διέφερε σημαντικά μεταξύ της ομάδας των ασθενών και των γυναικών ελέγχου (ρ=0.61). Αντίθετα, η κατανομή του πολυμορφισμού PAM 4G/5G διέρεφε μεταξύ των δύο ομάδων και ο ομόζυγος μεταλλαγμένος γονότυπος (4G/4G) είναι σπανιότερος στις ασθενείς από ό,τι στην ομάδα ελέγχου (ρ=0.014). Ανάλυση με τη μέθοδο της γραμμικής παλινδρόμησης (linear regresion) έδειξε ότι το επίπεδο της πρωτεΐνης C, η ομοζυγωτία για τον πολυμορφισμό και η ηλικία της ασθενούς είναι οι μόνοι σημαντικοί προγνωστικοί παράγοντες για τη δραστηριότητα του PAI. Η πρωτεΐνη C είναι υπεύθυνη για το 22% των μεταβολών της δραστηριότητας του PAI, ενώ ο γονότυπος 4G/4G μόνο για το 6%. Σε 74.2% των ασθενών του δείγματος μας (95% διάστημα εμπιστοσύνης 66.3 - 82.0) δε στάθηκε δυνατό να βρεθεί κάποιος αποδεκτός αιτιολογικός παράγοντας. Από την ομάδα αυτή, 41 γυναίκες πέτυχαν κύηση της οποίας είναι γνωστή η έκβαση σε διάστημα ενός έτους μετά τη διερεύνηση. Αν εξαιρέσουμε τις 2 περιπτώσεις στις οποίες σημειώθηκε εξωμήτριος κύηση, το συνολικό ποσοστό επιτυχίας ήταν 79.5% (95% διάστημα εμπιστοσύνης 66.8-92.1). Αν και το μικρό μέγεθος αυτής της ομάδας καθιστά απαγορευτική την επίσημη στατιστική ανάλυση, μία απλή περιγραφική ανάλυση δείχνει ότι η πρόγνωση σε επόμενη κύηση εξαρτάται κυρίως από την ηλικία της ασθενούς και τον αριθμό των προηγούμενων αποβολών
Transvaginal cervical length measurement for prediction of preterm birth in women with threatened preterm labor: a meta-analysis
Objectives: To integrate data on the performance of cervical length measurement for the prediction of preterm birth in symptomatic women. Methods: MEDLINE, SCOPUS and manual searches for studies with transvaginal ultrasound measurement of the cervical length in symptomatic women were carried out. Random effects models were used for data integration, and pooled test estimates of sensitivity, specificity, and positive and negative likelihood ratios (LR+ and LR-) were calculated along with their 95% CIs. Results: Twenty-eight studies fulfilled the selection criteria. For birth within 1 week from presentation, the pooled sensitivity, specificity, LR+ and LR- of cervical length <15 mm were 59.9% (95% CI, 52.7-66.8%), 90.5% (95% CI, 89.0-91.9%), 5.71 (95% CI, 3.77-8.65) and 0.51 (95% CI, 0.33-0.80), respectively. The same estimates for studies with presentation at or before 34 + 0 weeks were 71.0% (95% CI, 60.6-79.9%), 89.8% (95% CI, 87.4-91.9%), 5.19 (95% CI, 2.29-11.74) and 0.38 (95% CI, 0.11-1.34), respectively. For prediction of birth before 34 weeks, the pooled sensitivity, specificity, LR+ and LR- of cervical length <15 mm were 46.2% (95% CI, 34.8-57.8%), 93.7% (95% CI, 90.7-96.0%), 4.31 (95% CI, 2.73-6.82) and 0.63 (95% CI, 0.38-1.04), respectively. There was considerable heterogeneity across studies in most estimates. Conclusions: Measurement of cervical length in symptomatic women can detect a significant proportion of those who will deliver within 1 week and help to rationalize their management. The considerable heterogeneity across studies may be indicative of methodological flaws, which either were not reported at all or were underreported
Threatened miscarriage: evaluation and management
Threatened miscarriage—vaginal bleeding before 20
gestational weeks—is the commonest complication in
pregnancy, occurring in about a fifth of cases.w1 Miscarriage
is 2.6 times as likely,1 and 17% of cases are
expected to present complications later in pregnancy.2
Although general practitioners and gynaecologists
often see this condition, management of threatened
miscarriage is mostly empirical. Bed rest is routinely
recommended, and about a third of women presenting
with threatened miscarriage are prescribed drugs.w2
However, two thirds of the general practitioners
recommending this do not believe it affects outcome.3
In this review, we present available evidence on the
initial evaluation and management of threatened
miscarriage, focusing mainly on the first trimester of
pregnancy and primary healthcare settings
Synthesizing Evidence from Diagnostic Accuracy TEsts: The SEDATE guideline
Published by John Wiley & Sons Ltd.Although commonly overlooked during the writing and reporting process, most readers will look at only the abstract, so it is essential to convey as much quantitative information as possible, given the space limitations set by the journal. Suggested subheadings include 'Introduction' (specifying the current state of knowledge in the field, the gap that this study aims to cover, i.e. objectives), 'Methods' (search strategy, eligibility criteria, outcomes and statistical analysis), 'Results' (study selection and main results with numerical estimates) and 'Conclusion' (clinical interpretation of results and suggestions for future research)
Erratum: perinatal outcome in women treated with progesterone for the prevention of preterm birth: a meta-analysis
Neurodevelopmental Outcome of Fetuses with IncNreased Uchal Translucency and Apparently Normal Prenatal and/or Postnatal Assessment: a Systematic Review
Objectives: To systematically review and, when feasible, pool, published data regarding the prevalence of childhood neurodevelopmental delay in fetuses with increased first-trimester nuchal translucency (NT), normal karyotype and absence of structural defects or identifiable syndromes. Methods: MEDLINE and SCOPUS searches using combinations of the terms 'nuchal translucency' AND 'outcome*' were complemented by perusal of the references of the retrieved articles and an additional automated search using the 'search for related articles' PubMed function. Only children with a normal karyotype and no structural defects or syndromic abnormalities were included in the analysis. Between-studies heterogeneity was assessed using the I 2 statistic. Results: The total prevalence of developmental delay in all 17 studies was 28/2458 (1.14%; 95% CI, 0.79-1.64; I 2 = 57.6%). Eight studies (n = 1567) used NT > 99th centile as the cut-off; 15 children (0.96%; 95% CI, 0.58-1.58%) were reported as having developmental delay (I 2 = 72.2%). Four studies (n = 669) used the 95 th centile as the cut-off for increased NT; seven children (1.05%; 95% CI, 0.51-4.88%) were reported as having developmental delay (I 2 = 29.2%). Five studies used 3.0 mm as the cut-off for increased NT; the pooled rate of developmental delay was six of 222 children (2.70%; 95% CI, 1.24-5.77%; I 2 = 0.0%). Conclusion The rate of neurodevelopmental delay in children with increased fetal NT, a normal karyotype, normal anatomy and no identifiable genetic syndromes does not appear to be higher than that reported for the general population. More large-scale, prospective case-control studies would be needed to enhance the robustness of the results
Re: Transvaginal cervical length measurement for prediction of preterm birth in women with threatened preterm labor: A meta-analysis
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